A microparticle and/or nanoparticle separation, filtration and/or enriching device and method

Abstract

A microparticle and/or nanoparticle separation, filtration and/or enriching device. The device comprises a flow passage through which can be directed a liquid suspension supporting microparticles and/or nanoparticles therein, and at least one packed bed of particles physically retained within the flow passage through which can pass therethrough the liquid suspension. The device further comprises an ultrasonic actuation system for mechanically activating the or each packed bed during passage therethrough of the liquid suspension.

1 . A microparticle and/or nanoparticle separation, filtration and/or enriching device comprising:
 a flow passage through which can be directed a liquid suspension supporting microparticles and/or nanoparticles therein;   at least one packed bed of particles physically retained within the flow passage through which can pass therethrough the liquid suspension; and   an ultrasonic actuation system for mechanically activating the or each packed bed during passage therethrough of the liquid suspension.   
     
     
         2 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 1 , wherein the or each packed bed is formed from at least substantially uniformly sized, shaped particles having the same physical properties. 
     
     
         3 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 1  or  2 , wherein the particles are generally spherical in shape. 
     
     
         4 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 1  or  2 , wherein the particles are generally ellipsoidal, cylindrical, pillar or fibrous in shape. 
     
     
         5 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, wherein each particle is formed of a polymeric material. 
     
     
         6 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of  claims 1  to  4 , wherein each particle is formed of a metal, ceramic or crystal material. 
     
     
         7 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, wherein particles have a dimension measured in micrometres. 
     
     
         8 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of  claims 1  to  6 , wherein the particles have dimensions measured in millimetres. 
     
     
         9 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, wherein a plurality of said packed beds are provided, each packed bed being formed from particles of different shapes, dimensions and/or material properties. 
     
     
         10 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, wherein the or each packed bed is mechanically actuated at or near a resonance frequency of the particles forming the packed bed. 
     
     
         11 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according the  claim 10 , wherein a plurality of said packed beds are provided, each packed bed being mechanically actuated at a different resonance frequency, and or a different power level. 
     
     
         12 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according the  claim 10  or  11 , wherein, in the case of particles having a dimension (d), and the resonance frequency having a wavelength (λ), the first resonance frequency is approximately above d/λ≥0.25 (for spherical particles) and above d/λ≥0.20 (for cylindrical particles). 
     
     
         13 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 10  or  11 , wherein, in the case of spherical particles made from PS, the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one of said packed beds have a diameter (d) in the range of around less than 0.3λ to 0.67λ. 
     
     
         14 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 13 , wherein the or each said packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) of less than around 0.3λ. 
     
     
         15 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 13 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.3λ to 0.45λ. 
     
     
         16 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 13 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.45λ to 0.67λ. 
     
     
         17 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 10  or  11 , wherein, in the case of spherical particles made from PMMA, the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one of said packed beds have a diameter (d) in the range of around less than 0.32λ to 0.6λ. 
     
     
         18 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 17 , wherein the or each said packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) of less than around 0.32λ. 
     
     
         19 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 17 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.32λ to 0.415λ. 
     
     
         20 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 17 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.415λ to 0.6λ. 
     
     
         21 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, further comprising a packed bed retaining system for retaining the packed bed in position within the flow passage, while allowing the passage of microparticle and/or nanoparticles therethrough. 
     
     
         22 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 21 , wherein the flow passage is a microfluidic channel. 
     
     
         23 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 22 , wherein the bed retaining system comprises one or more micropillar posts extending along the flow passage downstream of the packed bed. 
     
     
         24 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to any one of the preceding claims, wherein the ultrasonic actuation device is a piezoelectric device. 
     
     
         25 . The microparticle and/or nanoparticle separation, filtration and/or enriching device according to  claim 24 , wherein the piezoelectric device is a surface acoustic wave (SAW) actuator. 
     
     
         25 . A method of separating, filtering and/or enriching microparticles and/or nanoparticles from a liquid suspension comprising:
 directing the liquid suspension through a flow passage within which is provided one or more packed beds of physically retained particles through which passes the liquid suspension; and   mechanically activating the or each bed while the liquid suspension passes through to thereby capture microparticles and/or nanoparticles within the or each packed bed.   
     
     
         26 . The method according to  claim 25 , wherein the or each packed bed is formed from at least substantially uniformly sized, shaped particles having the same physical properties. 
     
     
         27 . The method according to  claim 25  or  26 , wherein the particles are generally spherical in shape. 
     
     
         28 . The method according to  claim 25  or  26 , wherein the particles are generally ellipsoidal, cylindrical, pillar or fibrous in shape. 
     
     
         29 . The method according to any one of  claims 25  to  28 , wherein each particle is formed of a polymeric material. 
     
     
         30 . The method according to any one of  claims 25  to  28 , wherein each particle is formed of a metal, ceramic or crystal material. 
     
     
         31 . The method according to any one of  claims 25  to  30 , wherein particles have a dimension measured in micrometres. 
     
     
         32 . The method according to any one of  claims 25  to  30 , wherein the particles have dimensions measured in millimetres. 
     
     
         33 . The method according to any one of  claims 25  to  32 , wherein a plurality of said packed beds are provided, each packed bed being formed from particles of different shapes, dimensions and/or material properties. 
     
     
         34 . The method according to any one of  claims 25  to  33 , comprising mechanically actuating the or each packed bed at or near a resonance frequency of the particles forming the or each said packed bed. 
     
     
         35 . The method according the  claim 34 , comprising mechanically actuating a plurality of said packed beds, each packed bed being mechanically actuated at a different resonance frequency, and/or a different power level. 
     
     
         36 . The method according to  claim 34  or  35 , wherein, in the case of particles having a dimension (d), and the resonance frequency having a wavelength (l), the first resonance frequency is approximately above d/λ≥0.25 (for spherical particles) and above d/λ≥0.20 (for cylindrical particles). 
     
     
         37 . The method according to  claim 36 , comprising mechanically actuating the or said packed bed at a frequency having a wavelength (λ), said particles of the or at least one of said packed beds having a diameter (d) in the range of around less than 0.3λ to 0.67λ. 
     
     
         38 . The method according to  claim 36 , comprising mechanically actuating the or each said packed bed at a frequency having a wavelength (λ), said particles of the or at least one said packed bed having a diameter (d) of less than around 0.3λ. 
     
     
         39 . The method according to  claim 36 , comprising mechanically actuating the or each packed bed at a frequency having a wavelength (λ), said particles of the or at least one said packed bed having a diameter (d) in the range of around 0.3λ to 0.45λ. 
     
     
         40 . The method according to  claim 36 , comprising mechanically actuating the or each said packed bed at a frequency having a wavelength (λ), said particles having a diameter (d) in the range of around 0.45λ to 0.67λ. 
     
     
         41 . The method according to  claim 34  or  35 , wherein, in the case of spherical particles made from PMMA, the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one of said packed beds have a diameter (d) in the range of around less than 0.32λ to 0.6λ. 
     
     
         42 . The method according to  claim 41 , wherein the or each said packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) of less than around 0.32λ. 
     
     
         43 . The method according to  claim 41 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.32λ to 0.415λ. 
     
     
         44 . The method according to  claim 41 , wherein the or each packed bed is mechanically actuated at a frequency having a wavelength (λ), and said particles of the or at least one said packed bed have a diameter (d) in the range of around 0.415λ to 0.6λ. 
     
     
         45 . The method according to any one of  claims 25  to  44 , comprising intermittently suspending the mechanical activation of the or each packed bed to thereby release the captured microparticles and/or nanoparticles therefrom. 
     
     
         46 . The method according to any one of  claims 25  to  45 , comprising delivering batch volume of the liquid suspension through the flow passage. 
     
     
         47 . The method according to any one of  claims 25  to  45 , comprising delivering a continuous stream of the liquid suspension through the passage. 
     
     
         48 . The method according to any one of  claims 25  to  47 , wherein the nanoparticles are extracellular vesicles. 
     
     
         49 . The method according to  claim 48 , wherein the extracellular vesicles include apoptotic bodies and exosomes. 
     
     
         50 . The method according to any one of  claims 25  to  47 , wherein the liquid suspension is a contaminated water, and the nanoparticles are contaminants within the water. 
     
     
         51 . The method according to  claim 50  wherein the contaminants include viruses and/or bacteria. 
     
     
         52 . The method according to any one of  claims 25  to  47 , wherein the nanoparticles are precious metal or non-metal nanoparticles 
     
     
         53 . The method according to any one of  claims 25  to  47 , wherein the nanoparticles are DNA. 
     
     
         54 . A system for separating, filtering and/or enriching microparticles and/or nanoparticles from a liquid suspension, the system comprising:
 one or more processors;   memory comprising computer executable code, which when executed by the one or more processors, is configured to perform a filtration process and a subsequent collection process,   wherein during the filtration process, the one or more processors are configured to:   activate a first switch, wherein the first switch is configured to control fluid flow along a first conduit, the first conduit arranged to provide fluid communication between an outlet of a microparticle and/or nanoparticle separation, filtration and/or enriching device and a first receptacle, and whereby activating the first switch allows fluid flow between the outlet and the first receptacle; and   trigger an ultrasound signal to cause an ultrasonic transducer of the device to generate a sound wave to activate a packed bed of particles of the device, to thereby cause microparticles and/or nanoparticles of a liquid suspension to be trapped and collected inside the device and for filtered liquid to be conveyed along the first conduit to the receptacle; and   wherein during the collection process, the one or more processors are configured to:
 turn off the ultrasound signal to stop activation of the packed bed of particles of the device; and 
 deactivate the first switch to impede fluid flow between the outlet and the first receptacle; and 
 activate a second switch, wherein the second switch is configured to control fluid flow along a second conduit, the second conduit arranged to provide fluid communication between the outlet of the device and a second receptacle, and whereby activating the second switch allows fluid flow between the outlet and the second receptacle. 
   
     
     
         55 . The system of  claim 54 , wherein at the end of a collection process, the one or more processors are configured to execute computer code to cause the system to perform a subsequent filtration process and a subsequent collection process. 
     
     
         56 . The system of  claim 54  or  55 , wherein the microparticle and/or nanoparticle separation, filtration and/or enriching device comprises the microparticle and/or nanoparticle separation, filtration and/or enriching device of any one of  claims 1  to  24 . 
     
     
         57 . A method for separating, filtering and/or enriching microparticles and/or nanoparticles from a liquid suspension, the method comprising:
 a filtration process and a subsequent collection process,   wherein the filtration process comprises:
 activating a first switch, wherein the first switch is configured to control fluid flow along a first conduit, the first conduit arranged to provide fluid communication between an outlet of a microparticle and/or nanoparticle separation, filtration and/or enriching device and a first receptacle, and whereby activating the first switch allows fluid flow between the outlet and the first receptacle; and 
 triggering an ultrasound signal to cause an ultrasonic transducer of the device to generate a sound wave to activate a packed bed of particles of the device, to thereby cause microparticles and/or nanoparticles of a liquid suspension to be trapped and collected inside the device and for filtered liquid to be conveyed along the first conduit to the receptacle; and 
   wherein the collection process comprises:
 turning off the ultrasound signal to stop activation of the packed bed of particles of the device; and 
 deactivating the first switch to impede fluid flow between the outlet and the first receptacle; and 
 activating a second switch, wherein the second switch is configured to control fluid flow along a second conduit, the second conduit arranged to provide fluid communication between the outlet of the device and a second receptacle, and whereby activating the second switch allows fluid flow between the outlet and the second receptacle. 
   
     
     
         58 . The system of  claim 57 , wherein the method comprises performing a subsequent cycle of a filtration process and a subsequent collection process. 
     
     
         59 . A non-transitory machine-readable medium storing instructions which, when executed by one or more processors, cause a system to implement a method according to  claim 57  or  claim 58 .